ABSTRACT
Irritable bowel syndrome [IBS] was one of the most common functional gastrointestinal disorders. Psychological treatments have been effective in reducing symptoms severity and increasing mental health and well-being of these patients to some extent. The aim of this study was to determine the effectiveness of cognitive - behavioral stress management training on symptoms severity and psychological well-being of patients with IBS. The study was an experimental clinical trial with pretest - posttest design with control group. The subjects were 30 patients with IBS who were selected based on convenience sampling and were randomly divided into one experimental [N=15] and one control [N=15] group. there was a significant relation between symptoms severity and psychological wellbeing in two groups [p<0.001]. Cognitive - behavioral stress management training can be effective in reducing symptoms severity and improvement of mental health in patients with IBS and attention to the psychological situation of these patients is necessary